1. Field of the Invention
The present invention relates to a method for controlling the humidity inside a refrigerator, and a refrigerator adapted to carry out such method. The effectiveness of the food preservation performance of a refrigerator is mainly characterised by the level of its internal temperature and relative humidity level.
2. Description of the Related Art
In all the traditional domestic appliances the temperature is controlled by means of a dedicated temperature control system. Such control system is in general composed of one or more temperature sensors, one or more actuators (fan, compressors, etc), an user Interface allowing the customer to adjust the internal temperature and a temperature control algorithm. Such a traditional control algorithm will manage the cooling actuators according to the desired temperature and the actual temperature read by the sensor(s).
The internal relative humidity is not controlled in the known refrigerators and its level is the result of the following main factors:                refrigerator load        temperature control logic        cooling system,        user interaction (door opening length and frequency)        external condition (temperature, relative humidity etc.)        
The effects of these uncontrolled factors could get the internal refrigerator ambient too humid (with consequent undesired effects of condensation on the walls and with food damages, especially for the dairy products, due to build up of water on food surface and related quick growth of micro-organisms which reduce the shelf-life of refrigerated products) or too dry (with consequent dehydration of food, loss of weight and change of its organolectic properties, especially for fruit and vegetables).
In both cases the user has no possibility of changing the degree of humidity inside the refrigeration compartment, being well known that a “no frost” refrigerator has usually a refrigeration compartment with a very low relative humidity while a refrigeration compartment of a “direct cool” refrigerator has usually a high relative humidity which is usually higher than the optimal value for food proper conservation.